Prof - for the record, the first New Thiel team included audio industry insiders Bob Brown and long-time Thiel associate Steve Defuria. They lobbied for continuing Jim's designs and the CS1.7 and MCS1.7 were developed on their watch. A few of the original high-quality dealers came on board including Chicago area Audio Consultants. But the wagon never got rolling again. I suspect those 200s 2.7s may be the last of them. 1.7s probably have far fewer. BTW: I am investigating the 1.7 for upgrade parts for the entire CS1 series. Good reason to believe the drivers are highly optimized. Has anybody heard the CS1.7?
Regarding cap failure. Value drift is slow and steady and most audible via direct comparison with new. Since series feed caps block low-frequencies, as they drift the low end of the upper driver gets excess low frequency signal. Caps in tuned circuits (like notch filters) can drift to cause mis-match between the cause and the cure for erratic frequency response anomalies. And so forth and so on and on.
Failure, however, can come as severe driver distortion, but more commonly exhibits as 'breathing' noises and thunks and stutters.
Bottom line: replace your O2 electrolytic caps, even if with same as new. I don't have a schematic and my pair is not yet here. The O2 preceded our phase-induced esoteric education, so all caps may be electrolytic. And the wire and resistors are 'ordinary'. Whatever is in there is highly up-gradable. This year I'll be fetching my prototype pair and I'm pretty sure I won't be able to resist going down the upgrade path.
Todd - I would not think of tubes as a mis-match. Tubes do some things extraordinarily well. And even their weaknesses sound very nice. My first 'blown away' experience was Tim de Paravicini's big Esoteric Audio Research amp when we introduced the O3 at CES 1978. Awesome, before the word became diluted.
Regarding cap failure. Value drift is slow and steady and most audible via direct comparison with new. Since series feed caps block low-frequencies, as they drift the low end of the upper driver gets excess low frequency signal. Caps in tuned circuits (like notch filters) can drift to cause mis-match between the cause and the cure for erratic frequency response anomalies. And so forth and so on and on.
Failure, however, can come as severe driver distortion, but more commonly exhibits as 'breathing' noises and thunks and stutters.
Bottom line: replace your O2 electrolytic caps, even if with same as new. I don't have a schematic and my pair is not yet here. The O2 preceded our phase-induced esoteric education, so all caps may be electrolytic. And the wire and resistors are 'ordinary'. Whatever is in there is highly up-gradable. This year I'll be fetching my prototype pair and I'm pretty sure I won't be able to resist going down the upgrade path.
Todd - I would not think of tubes as a mis-match. Tubes do some things extraordinarily well. And even their weaknesses sound very nice. My first 'blown away' experience was Tim de Paravicini's big Esoteric Audio Research amp when we introduced the O3 at CES 1978. Awesome, before the word became diluted.